Trauma registries have been used in several states for occupational injury surveillance and research. Trauma registries have several advantages over hospital discharge data, including details about the injury and initial treatment and often a specific work-related field that allows identification of work-related injuries independent of paye. Significant upward trends (2003-2008) in age-adjusted rates of moderate/major work-related traumatic injury reports were found using the Washington State Trauma Registry (WTR), in contrast to flat trends when minor work-related traumatic injury reports were also included. Upward trends were particularly steep for Latinos. The National Center for Health Statistics Expert Group on Injury Severity Measurement stated, Trends in injury hospitalization discharges and emergency department visits represent a mixture of at least two effects: 1) trends in the incidence of injury 2) trends in service utilization and service delivery. Because both can vary over time...the incidence of injury would be better reflected by an indicator of the injury (e.g. injuries meeting a severity threshold) that is 'free' of extraneous factors like utiliation and service delivery. Inadequate severity characterization coupled with increasingly incomplete reporting or capture of minor work- related injuries over time may be contributing to an unwarranted optimism about overall trends in work-related injury rates. Specific Aim 1: Develop and submit a new occupational health surveillance indicator that can be based on trauma registry or hospital discharge data available in most states (Work-Related Traumatic Injury Hospitalizations) to the NIOSH-CSTE Occupational Health Surveillance Work Group. Using the National Hospital Discharge Survey and hospital discharge records from 4 states (AZ, FL, NJ, WA), assess: (1) whether identifying a stable subset of severe work-related nonfatal traumatic injuries by applying a severity restriction results in different trend estimates than those based o all hospitalized work-related nonfatal traumatic injuries, (2) whether trends diverge by race/ethnicity, and (3) whether particular injury types or causes may be driving trends. Specific Aim 2: Assess whether a state trauma registry with mandatory reporting requirements can serve as a reasonable approximation to a population-based database for the purposes of work-related nonfatal severe traumatic injury surveillance. In particular, assess whether Washington State hospital discharge data validate the upward trends in work-related severe traumatic injuries reported to the WTR, as well as the increased rates and trends among Latinos. Use this information in conjunction with information on changes in WTR inclusion criteria and changes in reporting hospitals to assess the relative representativeness of the WTR over time. Specific Aim 3: Link WTR and Washington State hospital discharge data to assess concordance for data fields, particularly relevant to occupational health services research, including payer, race/ethnicity, and ICD-9-CM external cause of injury codes (E-codes). Use the linked data to evaluate E-code based methods of identifying work-related injuries in hospital discharge records.